Coin Finishes

“Circulating,” “uncirculated,” “proof…” maybe you’ve heard these terms and wonder what it’s all about. Aren’t all coins made the same way?

Actually, they’re not. Different steps can be taken to produce different results. Here’s the story of how these coin finishes differ from each other and why they’re made the way they are.

Circulating

A circulating penny.

Circulating coins are also known as “business strikes.” They are made to circulate among people as they take care of their daily business of buying and selling, saving and collecting. These are the workhorses of the nation’s currency, and use only the basic steps that produce quality coinage.

Shipped in bags in large numbers, these coins rub against each other and may have some small dings before people even see them. Usually, that’s not a problem. Most people don’t mind if the coins they spend are a little scratched or dull from use. But for coin collectors, condition is an important factor.

Uncirculated

An uncirculated penny.

The United States Mint makes uncirculated coins for saving and collecting. They have the same designs as circulating coins, but they are not meant for daily use. They are for collectors, and are kept in far better condition than coins that have been handled every day.

In the past, after these coins were struck, they were put in special packaging instead of being dropped into large bags. The packaging kept them looking brand new and protected them from the wear and tear of handling.

But in 2005, uncirculated coins began being made with specially prepared dies so the coins would have a beautiful satin finish—smooth, but not as shiny as a proof. This finish makes it easier to tell a true uncirculated coin from a circulating coin that simply hasn’t circulated.

So, circulating coins are for spending and uncirculated for collecting. But for a coin that is the best example available of the coin maker’s art, there’s the proof coin.

Proof

A proof penny.

The first proof coins were most often made as a die test. Not many copies were made because not many were needed. But those that were made had to be made well.

In order to bring out every detail in the design, each proof coin was struck more than once. This extra care made proof coins even more beautiful than the circulating coins that came from those same dies. The proofs could then be examined closely to see that everything looked as planned. Once the proof was approved, the dies were used to make circulating coins, but striking them only one time.

This coin-stamping die is made like a photo negative, but instead of lights and darks being reversed, the highs and lows are reversed, as in a mold.

What happened to those special specimens? Some of those proof coins were used as a record, kept in archives for many years. Some were made for our nation to give as gifts to leaders of other nations. For example, our National Archives hold the first letters we have that talk about proof coins, which were called “specimen coins” or “master coins” at the time. Sets of proofs were put together in 1834 as gifts for the King of Siam and the Sultan of Muscatine.

United States Mint records show that, in 1858, sets of proof coins were offered for sale for the first time. The sets contained proof versions of all the circulating coins that were being made at the time, one of each denomination, as they do today.

James Snowden, then Director of the Mint, is said to be the one who made the term “proof coins” popular.

Proofs and Patterns

You may run across the term “pattern” in coin books. Both patterns and proofs were made in very small numbers. How were they different?

A pattern was made when a design hadn’t been fully decided on or a new metal alloy was being tried out, while a proof was made to test dies for a final design. Many patterns ended up as just patterns; their designs were never used on circulating coins and no more copies were made.

In other words, if the coins could talk, the proof would ask, “Am I ready to be copied and sent out into the world?” The pattern would ask, “Would I even be a good coin to make?”

Today’s Proofs

Today’s proof coins are prepared even more carefully than earlier proofs were. Specially-polished dies are used so these coins have a whole different look from circulating and uncirculated coins. The field (background) on a modern proof coin is polished so that it’s very smooth and shiny, almost like a mirror. The raised parts have a “frosted” finish, so they stand out from the background. The highest level of technology is used to produce the best possible results.

Today’s proofs are made as carefully as pieces of expensive jewelry. Imperfect coins are melted down, while those that pass inspection are ultrasonically sealed in plastic. The dies that make proofs are now used for making only proofs, not circulating coins.

Proofs are made and sold regularly today, while in the past, they were made only when they were needed to test circulating coin dies. But there’s one thing that modern proofs have in common with old-style proofs: the coins are struck more than once to get the sharpest images and bring out every bit of detail that the artist put in.

Proof finishes are used for commemorative coins as well as circulating coins. Although commemoratives are legal tender, you wouldn’t want to spend them because they cost more than their face value. But you might want to collect them. Their look is truly striking!